Compulsive sexual behavior is defined as behavior driven by anxiety reduction mechanisms rather than by sexual desire. Obsessive thoughts and compulsive behaviors reduce anxiety and distress but create a self-perpetuating cycle. Sexual activity provides temporary relief, but it is followed by further distress. The concern about CSB as a problem to be identified and treated has been heightened by the current HIV epidemic. Of the many manifestations of CSB, paraphilic behaviors constitute unconventional sexual behaviors that are compulsive and thus devoid of love and intimacy. Nonparaphilic CSB involves conventional and normative sexual behaviors taken to a compulsive extreme. The author estimates that CSB occurs in about 5 percent of the population. More men than women have identified themselves with CSB, but this may be due to society's restrictive definition of sexuality or because society tends to define sexuality from a masculine perspective. Most patients will not identify CSB as a presenting problem. CSB may be diagnosed by looking for associated symptoms and illnesses, such as anxiety, depression, alcohol or drug abuse, sexually transmitted diseases, unwanted pregnancies, somatic complaints, relationship discord, sexual dysfunction, and child abuse. CSB has been strongly linked to early childhood trauma or abuse, highly restricted environments regarding sexuality, dysfunctional attitudes about sex and intimacy, low self-esteem, anxiety, and depression. Patients who suffer from CSB can be helped through a combination of psychotherapy and pharmacotherapy. Sex therapists must know how to evaluate and treat general mental disorders and substance abuse problems. 29 references and 4 tables